English
Related papers

Related papers: {\it Ab--initio} finite temperature excitons

200 papers

We show that the coupling to vibrational degrees of freedom can drive a semimetal excitonic-insulator quantum phase transition in an one-dimensional two-band f-c electron system at zero temperature. The insulating state typifies an…

Strongly Correlated Electrons · Physics 2015-06-17 N. V. Phan , K. W. Becker , H. Fehske

In this work, we develop an optomechanical formalism for macroscopic quantum states in exciton-polariton systems with strong exciton-phonon interactions. We show that polariton optomechanical interactions induce dynamical backaction,…

Quantum Gases · Physics 2024-10-31 Vladislav Yu. Shishkov , Evgeny S. Andrianov , Anton V. Zasedatelev

When atoms are loaded into an optical lattice, the process of gradually turning on the lattice is almost adiabatic. In this paper we investigate how the temperature changes when going from the gapless superfluid phase to the gapped Mott…

Statistical Mechanics · Physics 2010-09-10 Lode Pollet , Corinna Kollath , Kris Van Houcke , Matthias Troyer

The ultrafast conversion of coherent excitons into incoherent excitons, as well as the subsequent exciton diffusion and thermalization, are central topics in current scientific research due to their relevance in optoelectronics,…

Materials Science · Physics 2025-01-15 Gianluca Stefanucci , Enrico Perfetto

Ultracold polar molecules trapped on an optical lattice is a many-body system that, under appropriate conditions, may support collective excitations reminiscent of excitons in solid state crystals. Here, we discuss the rotational…

Atomic Physics · Physics 2017-08-23 Marina Litinskaya , Roman V. Krems

The interaction between off-resonant laser pulses and excitons in monolayer transition metal dichalcogenides is attracting increasing interest as a route for the valley-selective coherent control of the exciton properties. Here, we extend…

The properties of excitons, or correlated electron-hole pairs, are of paramount importance to optoelectronic applications of materials. A central component of exciton physics is the electron-hole interaction, which is commonly treated as…

We examine the absorption spectrum of electromagnetic radiation from excitons, where an exciton in the $1s$ state absorbs a photon and makes a transition to the $2p$ state. We demonstrate that the absorption spectrum depends strongly on the…

Condensed Matter · Physics 2009-10-31 K. Johnsen , G. M. Kavoulakis

We report that dark excitons can have a large contribution to the emission intensity in carbon nanotubes due to an efficient exciton conversion from a dark state to a bright state. Time-resolved photoluminescence measurements are used to…

Mesoscale and Nanoscale Physics · Physics 2019-12-11 A. Ishii , H. Machiya , Y. K. Kato

We show that a quasi-two dimensional condensate of optically active excitons emits coherent light even in the absence of population inversion. This allows an unambiguous and clear experimental detection of the condensed phase. We prove…

Condensed Matter · Physics 2015-06-25 J. Fernandez-Rossier , C. Tejedor , R. Merlin

Anatase TiO$_2$ is among the most studied materials for light-energy conversion applications, but the nature of its fundamental charge excitations is still unknown. Yet it is crucial to establish whether light absorption creates…

The photoluminescence (PL) and absorption experiments have been performed in GaSe slab with incident light polarized perpendicular to c-axis of sample at 10K. An obvious energy difference of about 34meV between exciton absorption peak and…

Mesoscale and Nanoscale Physics · Physics 2016-03-08 Chengrong Wei , Xi Chen , Dian Li , Huimin Su , Jun-Feng Dai

We study spin dynamics of excitons confined in self-assembled CdSe quantum dots by means of optical orientation in magnetic field. At zero field the exciton emission from QDs populated via LO phonon-assisted absorption shows a circular…

Materials Science · Physics 2015-06-24 S. Mackowski , T. Gurung , H. E. Jackson , L. M. Smith , J. K. Furdyna , M. Dobrowolska

We study carrier interaction induced many-body effects on the excitonic optical properties of highly photoexcited one-dimensional semiconductor quantum wire systems by solving the dynamically screened Bethe-Salpeter equation using realistic…

Strongly Correlated Electrons · Physics 2009-11-07 D. W. Wang , S. Das Sarma

We propose optical means to reveal the presence of a dark exciton condensate that does not yield any photoluminescence at all. We show that (i) the dark exciton density can be obtained from the blueshift of the excitonic absorption line…

Quantum Gases · Physics 2015-06-16 M. Combescot , R. Combescot , M. Alloing , F. Dubin

Absorption and emission of pristine-like semiconducting monolayers of BN, AlN, GaN, and InN are here systematically studied by ab-initio methods. We calculate the absorption spectra for in-plane and out-of-plane light polarization including…

Rotational excitation of polar molecules trapped in an optical lattice gives rise to rotational excitons. Here we show that non-linear interactions of such excitons can be controlled by an electric field. The exciton--exciton interactions…

Mesoscale and Nanoscale Physics · Physics 2012-06-20 Ping Xiang , Marina Litinskaya , Roman V. Krems

We study a two-species Bose-Einstein condensates confined in quasi-two-dimensional (quasi-2D) optical lattices at finite temperatures, employing the Hartree-Fock-Bogoliubov theory with the Popov approximation. We examine the role of thermal…

Quantum Gases · Physics 2020-07-22 K. Suthar , D. Angom

Exciton-polaritons in semiconductor microcavities have advanced to become a model system for studying dynamical Bose-Einstein condensation, macroscopic coherence, many-body effects, nonclassical states of light and matter, and possibly…

Quantum Gases · Physics 2017-03-21 C. Schneider , K. Winkler , M. D. Fraser , M. Kamp , Y. Yamamoto , E. A. Ostrovskaya , S. Hoefling

We study systematically the role of temperature in the optical response of doped two-dimensional semiconductors. By making use of a finite-temperature Fermi-polaron theory, we reveal a crossover from a quantum-degenerate regime with…

Mesoscale and Nanoscale Physics · Physics 2024-01-25 A. Tiene , B. C. Mulkerin , J. Levinsen , M. M. Parish , F. M. Marchetti